package com.ruoyi.ai.service.disableword;


import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;


//敏感词过滤器：利用DFA算法  进行敏感词过滤


@SuppressWarnings("rawtypes")
public class SensitiveFilterService {


    private Map sensitiveWordMap = null;


    // 最小匹配规则
    public static int minMatchTYpe = 1;


    // 最大匹配规则
    public static int maxMatchType = 2;


    // 单例
    private static SensitiveFilterService instance = null;


    // 构造函数，初始化敏感词库
    private SensitiveFilterService() {


        sensitiveWordMap = new SensitiveWordInit().initKeyWord();
    }


    // 获取单例
    public static SensitiveFilterService getInstance() {
        if (null == instance) {
            instance = new SensitiveFilterService();
        }
        return instance;
    }


// 获取文字中的敏感词


    public Set<String> getSensitiveWord(String txt, int matchType) {
        Set<String> sensitiveWordList = new HashSet<String>();


        for (int i = 0; i < txt.length(); i++) {


// 判断是否包含敏感字符
            int length = CheckSensitiveWord(txt, i, matchType);

// 存在,加入list中
            if (length > 0) {
                sensitiveWordList.add(txt.substring(i, i + length));

// 减1的原因，是因为for会自增
                i = i + length - 1;
            }
        }

        return sensitiveWordList;
    }
// 替换敏感字字符

    public String replaceSensitiveWord(String txt, int matchType,
                                       String replaceChar) {
        String resultTxt = txt;
// 获取所有的敏感词
        Set<String> set = getSensitiveWord(txt, matchType);
        Iterator<String> iterator = set.iterator();
        String word = null;
        String replaceString = null;
        while (iterator.hasNext()) {
            word = iterator.next();
            replaceString = getReplaceChars(replaceChar, word.length());
            resultTxt = resultTxt.replaceAll(word, replaceString);
        }
        return resultTxt;
    }

 /**
     * 返回 字符串含有的拦截词  逗号隔开
     *
     * @param txt
     * @return
     */
    public String returnSensitiveWord(String txt) {
        String resultTxt = txt;
        StringBuilder sensitiveWord = new StringBuilder("");
        // 获取所有的敏感词
        Set<String> set = getSensitiveWord(txt, 1);
        Iterator<String> iterator = set.iterator();
        String word = null;
        String replaceString = null;
        while (iterator.hasNext()) {
            String str = resultTxt;
            word = iterator.next();
            replaceString = getReplaceChars("*", word.length());
            resultTxt = resultTxt.replaceAll(word, replaceString);
            if (!resultTxt.equals(str)){
                sensitiveWord.append(word);
                sensitiveWord.append(",");
            }
        }
        return sensitiveWord.toString();
    }
    /**
     * 获取替换字符串

     *
     * @param replaceChar
     * @param length
     * @return
     */
    private String getReplaceChars(String replaceChar, int length) {
        String resultReplace = replaceChar;
        for (int i = 1; i < length; i++) {
            resultReplace += replaceChar;
        }

        return resultReplace;
    }

  /**
     * 判断文本中包含敏感词个数
     * @param
     */
    public static boolean checkContainCount(String txt) {
        SensitiveFilterService filter = SensitiveFilterService.getInstance();
        Set<java.lang.String> hou = filter.getSensitiveWord(txt, 1);
        return hou.size() > 0;
    }
    /**

     * 检查文字中是否包含敏感字符，检查规则如下：<br>
     * 如果存在，则返回敏感词字符的长度，不存在返回0
     *
     * @param txt
     * @param beginIndex
     * @param matchType
     * @return
     */
    public int CheckSensitiveWord(String txt, int beginIndex, int matchType) {

// 敏感词结束标识位：用于敏感词只有1位的情况
        boolean flag = false;

// 匹配标识数默认为0
        int matchFlag = 0;
        Map nowMap = sensitiveWordMap;
        for (int i = beginIndex; i < txt.length(); i++) {
            char word = txt.charAt(i);
// 获取指定key
            nowMap = (Map) nowMap.get(word);

// 存在，则判断是否为最后一个
            if (nowMap != null) {

// 找到相应key，匹配标识+1
                matchFlag++;

// 如果为最后一个匹配规则,结束循环，返回匹配标识数
                if ("1".equals(nowMap.get("isEnd"))) {

// 结束标志位为true
                    flag = true;

// 最小规则，直接返回,最大规则还需继续查找
                    if (SensitiveFilterService.minMatchTYpe == matchType) {
                        break;
                    }
                }
            }


// 不存在，直接返回
            else {
                break;
            }
        }


        if (matchFlag < 2 && !flag) { // 长度必须大于等于1，为词
            matchFlag = 0;
        }
        return matchFlag;
    }


}


